Mapped operation Transforms for sequential objectMode streams (e.g. timeseries data). Contains a set of stream Transforms that accept ordered objectMode streams with a sequenceKey perform an operation on each value in each record.

Most of these operations are shallow, that is they will not descend into nested keys at each record.

Apply fn to each value in each record, leaving the sequence key seqKey alone. Walks through each record calling fn for each value, so fn should accept a value and return what you would like the new value to be.

Replace the record with a new record which is at the key or key path specified by path and optionally rename the key to name. Use this to convert timeseries with partitioned or nested data into specific portions of each record only. path accepts js dot notation, e.g. into("v", "foo.bar[2]") would find in each record a property named foo, in each of those objects a property named bar which stores an array, then from that array take the 3rd element only.